1. Field of the Invention
The invention concerns improvements in surgical retractors, the word "retractors" being here used to encompass any surgical tool that can be used to retract soft tissue within an incision, e.g., depressers, elevators, dissectors, and spatulas.
2. Description of the Related Art
Any incision for a surgical operation should be as narrow as possible, both to minimize post-operative trauma and also to leave the smallest possible scar. On the other hand, it sometimes is desirable to maintain an appreciable spacing between two surgical implements that have been inserted into the incision. For example, when using an electro-surgical instrument to produce highly localized heat for cutting or coagulating tissue, it usually is necessary to retract elements such as nerves, both to provide access and also to protect the retracted elements from the heat. lnasmuch as surgical retractors are metallic and conduct heat and electricity, great care must be exercised to maintain a spacing such that the electro-surgical instrument does not heat the retractor and thus damage tissue being contacted by the retractor.
Regardless of the size of the incision, there can be a problem in maintaining sufficient spacing between tissue to be cut or coagulated and other tissue. To illustrate, it sometimes is necessary to cauterize bleeding tissue located directly beneath a nerve which can be moved only a tiny distance without danger of being damaged, thus requiring the cauterizing instrument to be moved into close proximity to the retractor.
I suppose that consideration has been given to applying electrically and/or thermally insulating coatings such as "Teflon" or an enamel to surgical retractors, but such thoughts, if expressed, have probably been dismissed as impractical for reasons such as the need for any such coating to withstand sterilization procedures. Furthermore, any such coating would need to be resistant to abrasion inasmuch as surgical retractors often are used in conjunction with powered burs or with other steel instruments such as knives. In any event, I have never seen an electrically insulated surgical retractor of any kind nor one whose surface is resistant to cutting by a steel instrument.